I agree with russ-d, not only because he is a mazda maniac guru of the guru's bad a-- mo fo, but also because I too have had a b2600i with those same simptoms, and it was cracked head! I tried the computer and even though mine had bad capacitors, it still RLS after replacing the ecm with a reman one. Dump that b2600i off in your local pond and get a KIA MOTOR! haha!